The invention relates to the electronic stabilization of the images captured by an observation apparatus of an imaging system, such as portable thermal observation binoculars or observation or guidance cameras.
The carrier of the apparatus, whether it be a person or a weapon, may be in motion, on the one hand, and create all kinds of vibrations, on the other hand, and, from a certain magnification onwards, one no longer sees anything on the images which are too blurred. They must then be stabilized in order to circumvent the effects related to the trajectory of the carrier and also those caused by the vibrations to which the apparatus is subjected, in short, to compensate for the 3D motions of the apparatus.
Within the context of the present patent application, stabilization will be regarded as involving the mutual registration of the successive images supplied by the observation apparatus. More precisely, image k+1 differing from image k owing to rotations in roll, pitch and yaw, change of focal length (in the case of a camera whose zoom factor may be varied), translations and angular and linear vibrations, it is necessary to impose opposite zoom factors and rotations in order to stabilize image k+1 with respect to image k.
To do this, it is already known how to determine these rotations but via gyroscopic means based on an inertial reference frame. These are excessively powerful means. The applicant has sought a much less unwieldy and cheap solution and thus proposes his invention.